#!/bin/bash
#
# /etc/init.d/elasticsearch -- startup script for Elasticsearch
#
### BEGIN INIT INFO
# Provides:          elasticsearch
# Required-Start:    $network $remote_fs $named
# Required-Stop:     $network $remote_fs $named
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Starts elasticsearch
# Description:       Starts elasticsearch using start-stop-daemon
### END INIT INFO

PATH=/bin:/usr/bin:/sbin:/usr/sbin
NAME=elasticsearch
DESC="Elasticsearch Server"
DEFAULT=/etc/default/$NAME

if [ `id -u` -ne 0 ]; then
    echo "You need root privileges to run this script"
    exit 1
fi


. /lib/lsb/init-functions

if [ -r /etc/default/rcS ]; then
        . /etc/default/rcS
fi


# The following variables can be overwritten in $DEFAULT

# Run Elasticsearch as this user ID and group ID
ES_USER=elasticsearch
ES_GROUP=elasticsearch

# Directory where the Elasticsearch binary distribution resides
ES_HOME=

# Directory containing Java
ES_JAVA_HOME=$ES_HOME/jdk

# Additional Java OPTS
#ES_JAVA_OPTS=

# Maximum number of open files
#MAX_OPEN_FILES=65536

# Maximum amount of locked memory
#MAX_LOCKED_MEMORY=

# Elasticsearch log directory
LOG_DIR=/var/log/$NAME

# Elasticsearch data directory
DATA_DIR=/var/lib/$NAME

# Elasticsearch configuration directory
ES_PATH_CONF=/etc/$NAME

# Maximum number of VMA (Virtual Memory Areas) a process can own
#MAX_MAP_COUNT=262144

# Elasticsearch PID file directory
PID_DIR="/var/run/elasticsearch"

# End of variables that can be overwritten in $DEFAULT

# overwrite settings from default file
if [ -f "$DEFAULT" ]; then
    . "$DEFAULT"
fi

# Define other required variables
PID_FILE="$PID_DIR/$NAME.pid"
DAEMON=$ES_HOME/bin/elasticsearch
DAEMON_OPTS="-d -p $PID_FILE -Epath.logs=$LOG_DIR -Epath.data=$DATA_DIR"
DAEMON_ENV_VARS="ES_PATH_CONF=$ES_PATH_CONF"

export ES_JAVA_OPTS
export JAVA_HOME
export ES_INCLUDE
export ES_JVM_OPTIONS

if [ ! -x "$DAEMON" ]; then
    echo "The elasticsearch startup script does not exists or it is not executable, tried: $DAEMON"
    exit 1
fi

checkJava() {
    if [ -x "$JAVA_HOME/bin/java" ]; then
        JAVA="$JAVA_HOME/bin/java"
    else
        JAVA=`which java`
    fi

    if [ ! -x "$JAVA" ]; then
        echo "Could not find any executable java binary. Please install java in your PATH or set JAVA_HOME"
        exit 1
    fi
}

case "$1" in
  start)
        checkJava

        log_daemon_msg "Starting $DESC"

        pid=`pidofproc -p $PID_FILE elasticsearch`
        if [ -n "$pid" ] ; then
            log_begin_msg "Already running."
            log_end_msg 0
            exit 0
        fi

        # Ensure that the PID_DIR exists (it is cleaned at OS startup time)
        if [ -n "$PID_DIR" ] && [ ! -e "$PID_DIR" ]; then
            mkdir -p "$PID_DIR" && chown "$ES_USER":"$ES_GROUP" "$PID_DIR"
        fi
        if [ -n "$PID_FILE" ] && [ ! -e "$PID_FILE" ]; then
            touch "$PID_FILE" && chown "$ES_USER":"$ES_GROUP" "$PID_FILE"
        fi

        if [ -n "$MAX_OPEN_FILES" ]; then
            ulimit -n $MAX_OPEN_FILES
        fi

        if [ -n "$MAX_LOCKED_MEMORY" ]; then
            ulimit -l $MAX_LOCKED_MEMORY
        fi

        if [ -n "$MAX_MAP_COUNT" ]; then
            sysctl -q -w vm.max_map_count=$MAX_MAP_COUNT
        fi

        # Start Daemon
        start-stop-daemon -d $ES_HOME --start --user "$ES_USER" -c "$ES_USER" --pidfile "$PID_FILE" \
            --exec /usr/bin/env $DAEMON_ENV_VARS $DAEMON -- $DAEMON_OPTS
        return=$?
        if [ $return -eq 0 ]; then
            i=0
            timeout=10
            # Wait for the process to be properly started before exiting
            until { kill -0 `cat "$PID_FILE"`; } >/dev/null 2>&1
            do
                sleep 1
                i=$(($i + 1))
                if [ $i -gt $timeout ]; then
                    log_end_msg 1
                    exit 1
                fi
                done
        fi
        log_end_msg $return
        exit $return
        ;;
  stop)
        log_daemon_msg "Stopping $DESC"

        if [ -f "$PID_FILE" ]; then
            start-stop-daemon --stop --pidfile "$PID_FILE" \
                --user "$ES_USER" \
                --quiet \
                --retry TERM/60/KILL/5 > /dev/null
            if [ $? -eq 1 ]; then
                log_progress_msg "$DESC is not running but pid file exists, cleaning up"
            elif [ $? -eq 3 ]; then
                PID="`cat $PID_FILE`"
                log_failure_msg "Failed to stop $DESC (pid $PID)"
                exit 1
            fi
            rm -f "$PID_FILE"
        else
            log_progress_msg "(not running)"
        fi
        log_end_msg 0
        ;;
  status)
        status_of_proc -p $PID_FILE elasticsearch elasticsearch && exit 0 || exit $?
        ;;
  restart|force-reload)
        if [ -f "$PID_FILE" ]; then
            $0 stop
        fi
        $0 start
        ;;
  *)
        log_success_msg "Usage: $0 {start|stop|restart|force-reload|status}"
        exit 1
        ;;
esac

exit 0
